Got a weird problem with my FX-8120. Lately, it doesn't want to ramp up it's clockspeed to my overclock settings and as a result, gaming is a PITA. The CPU has an overclock manually forced to 24 * 200 to 4.8Ghz with a 1.565 voltage (I got a decent cooler + case, temps stay 35-50C loaded).

When the system boots up, it shows the OC settings on POST screen, and im assuming it boots to those. I get to Windows, and it feels slow. I open up CPU-Z and it says 7 * 200 for 1.4Ghz with a 1.306 voltage. MSI's Control Centre 5 also reports this clockspeed, and forcing 8 threads of work thru Prime95 doesn't force it to clock up neither. Temps would indicate that the CPU really is at 1.4Ghz when I use Prime95 as it barely hits high 20's - It's simply too low if the OC was being apply with that voltage.

I've turned off (and always have since I got it) all the TurboCore, Core Park, Core Control and CPU Power Phase stuff in BIOS as these do cause issues when you OC.

This isn't really the proper way as this shouldn't be able to slow your CPU in theory, but it happened on y 8120...what is your windows power profile set to for minimum/maximum CPU speed percentage? you could try forcing it to 100% and see if you get the full speed that way. As I said, this shouldn't be an issue, but it could help if it's set to something like 5% and it's easy to check.

I clear CMOS again, and set up the OC again from scratch and re-booted. It is still seemingly ignored.I've re-flashed the BIOS (there was actually a newer version). After turning all the usuals mentioned in my OP it still ignores the OC.I've booted into my Ubuntu partition. It's reporting the same speed as Windows (1.4Ghz).

The comment about Windows Power Management - You might be onto something there but it's confusing me. The power plan is High Performance, but there's no CPU settings for min freq, max freq and cooling policy like I remember on PC's of old. A quick search on Google reveals that this is normal. Instead, the options for CPU power are actually within the Radeon Drivers CP under the AMD Vision >> Overdrive >> CPU Overdrive options. This says min speed 100% for CPU, but it doesn't show my OC - It says the CPU is at 3.1Ghz (Stock). It's not, as other's report it's still at 1.4Ghz.

I winder if this is causing a problem, but if so I don't know how to go about it as you can;t seemingly turn it off, and why would it be overiding the BIOS?

So, im willing to try anything else before I start swapping out the CPU for another one, or testing a new motherboard, or rolling back to drivers that never included this stuff (whenever that was)...

When it's at stock clocks, it behaves like it's supposed to. It will dynamically clock up and down. It does spend a lot of time at 1.4Ghz when idle, but it's supposed to do that. A quick execution of Prime95 though and it ramps up to 3.1Ghz just fine.

Worth noting is though, it does this at stock settings while all the time turbocore and all the dynamic clock stuff and core parking are still turned off in BIOS. They are also off in Windows in the Vision Centre CP, as the CPU is set to not go below 100% clockspeed - So it should not clock down at all, regardless of load.

As soon as the OC is apply, it will just go back to sticking at 1.4Ghz regardless of workload. It's very odd.

If cool n'Quite and other power saving schemes are on, then the CPU frequency should stay way under the stock rated frequency during idle or low load. It should increase clock speed according to load. Have you used OCCT yet? You can use it to stress test the CPU and it shows you the highest/lowest and current specs of the CPU (like voltage, frequency etc). Sorry if i''m underestimating your expertise, i admit i did not read the posts, mostly skimped them. There was some mentioning of Linux but i have no idea what stress tools are available for it. Regardless if the OC is done in the BIOS the OS should not influence the end result afaik....

Edit:Another avenue for troubleshooting would be to check the temperature of the CPU. Maybe it's throtling due to overheating, maybe the heatsink (you're using stock or aftermarket?) is not capable enough or it's not making a good contact with the CPU....

nVidia video drivers FAIL, click for more infoDisclaimer: All answers and suggestions are provided by an enthusiastic amateur and are therefore without warranty either explicit or implicit. Basically you use my suggestions at your own risk.

On Ubuntu I use CPUBurn - Just somnething simple enough to induce an eye-watering workload for the CPU to munch thru...

Anyway, I can't find anything for CnQ in my BIOS or in Windows. I also thought that windows and BIOS remain seperate, but rest assured this isn't the case with this board and CPU combo.

The FX-8120 CPU, it's 990FX Chipset and BIOS and the Radeon's 6950 can all be micro-modified to a very detailed level in AMD's own "Vision Engine CP". This driver suite replaced a long time ago what used to be called the Catalyst Control Centre (and even then it only delt with graphics). I can call up, modify and write back many CPU and memory BIOS values in there - It seems to manage everything.

Have you tried a lower OC, say 4.6 GHz? Maybe the motherboard has decided (for whatever reason) that this system can't do 4.8 GHz any more, and is falling back to 1.4 GHz as some sort of failsafe?

Beyond that, all I can really think of is trying the CPU in a different system to try and rule in/out the CPU as the source of the problem. I'm sort of leaning towards the problem being the motherboard, but it could be almost anything...

The years just pass like trains. I wave, but they don't slow down.-- Steven Wilson

I have to agree with just brew it about the motherboard. Have you tried setting it back to stock and upping the multiplier by one every time? Maybe it is a BIOS failsafe and you might be able to see where it kicks in if you up your CPU speed one step at a time. If it'll only get to 4.2GHz now, you should see that by slowly upping the speed.

I've been busy over the past few days trying to get to the bottom of this. I firstly:- Removed all AMD control software and drivers. Removed all MSI motherboard tweaking and monitoring tools. Ran driver sweeper and then re-installed newest AMD/Radeon drivers only (12.11 BETA)

It made no difference to the clockspeed problem, so then:- Removed the FX-8120 and stole the Athlon II 640 from my HTPC and put that in this mobo.

This CPU works, it can't OC to well - But I just ramped it's FSB up to 3.4Ghz (this CPU is multiplier locked) and bumped up the vCore a touch and well, and lowered the RAM clock (It don't support 1866Mhz)...

...And it idles at 800Mhz, and as soon as it detects a stressful workload it bumps it's FSB to the rated 3.4Ghz I set it to. The FX *used* to do this.

I can't test my FX in another mobo though, as the board in my HTPC can't run FX CPU's - But my board seems to be ok, right - So the CPU might be a bit dodgy???

Not necessarily. I think you'd have to test your CPU in another board or another 8-core FX proc in this mobo to truly find out. The processor you are testing is a 95W processor with half the int cores and the one that doesn't work is 125W. If the Power Stage was starting to fail on your motherboard for instance, you may not see it on the Athlon II you installed in my opinion. Plus, while it's not unheard of by any means, it's much more rare that the processor is bad vs. motherboard/memory/power supply. Do you have any buddies that have an AM3+ motherboard you could at least test it with?

However, that Athlon II isn't a bad stopgap processor, I'll bet you could at least take a break and get some gaming in, eh?

Oh, yeah - The slightest hint of a multiplier change on the FX from stock causes it to stay at 1.4Ghz? I'm trying to source another mobo to test it in as per RedAdmiral's suggestion.

At the moment, I'm using my Athlon II 640. It's a little embarassing for the FX but i've been playing games on it. Unrelated to this topic but FPS in the new NFS Most Wanted game is higher by 2-5 fps as a minimum at it's stock setting. Hmmm...